fast-breaking developments in egypt. Fears of more violence, after the country's first democratically-elected president is reportedly in military custody. Abc's byron pitts is in cairo, where there are calls for more protests today. A lot of uncertainty there. Byron? Reporter: Good morning, lara. We're by tahrir square, where the crowd is getting larger and louder than normal today. They expect more violence, especially today, on what the locals call the day of rejection. Fortifying their strongholds, the muslim brotherhood has made clear they're not ready to go home or give in, to what is a new reality in egypt. Look closely to the left of your screen. Members of the brotherhood charge a lone egyptian soldier. They swarm like bees. Another soldier tries to intervene. And he, too, was tackled to the ground. Morsi is -- Reporter: If anger is the language of the defeat. Raucous raw jubilation goes to the ticketer. Tahrir square has the look and feel of times square on new year's eve. Millions believing this is another new step on the journey towards democracy in egypt. Interim president adly mansour. He was hand picked by the military. He called the muslim brotherhood, part of the fabric of an egyptian society. While he sounded like a leader with reconciliation, members of the military were rounding up members of muslim brotherhood. President morsi is under arrest, as are key cabinet members, like his national security minister. He voiced the frustration of the people, not in the mood of reconciliation. I'm wanting to bring democracy to this country. If I'm killed in the process, that's a price I'm willing to pay. Reporter: I wanted to ask him, would their demonstration be peaceful? He snapped, why ask me? Ask the other side. I looked to the back of the room and one of his man was adding a fresh batch of nails to his wooden club. We're going to turn to the cold case gaining some heat.

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